Many devices today include multiple integrated circuit (IC) chips to carry out their designed for functionalities. These IC chips often need to communicate with each other at very high data rates. For example, complex devices can include several IC chips on a printed-circuit board (PCB) that are required to communicate with each other at rates exceeding several gigabits per second (Gb/s), and these rates continue to increase with each new generation of devices. At such high rates, communication over electrical traces on a PCB becomes difficult due to, for example, impedance mismatches, the skin effect, and dielectric absorption, all of which lead to distortion and/or attenuation of a transmitted signal. Moreover, depending on the number of IC chips used, routing of electrical traces between the IC chips can be difficult on a PCB with limited area.
Wireless communication can be used to overcome the problems of electrical interconnection described above. For example, wireless communication is generally not constrained by PCB area limitations and enough unlicensed wireless spectrum exists to accommodate high data rates in the multi Gb/s range. In particular, there is 7 GHz of spectrum available for unlicensed wireless communication in the 60 GHz band, from 57-64 GHz in the United States and Canada and from 59-66 GHz in Japan. This spectrum can be used to accommodate high data rate wireless chip-to-chip communications in the multi Gb/s range.
However, for any such wireless chip-to-chip communication solution, and potentially for other, longer range, communication solutions (e.g., several meters or several tens of meters) for device-to-device communication, it is desirable that the required hardware be compact and cheap. Current solutions for wireless chip-to-chip and device-to-device communication typically fail to achieve one or both of these often competing criteria by using off-chip components and/or expensive IC processes, such as Gallium Arsenide (GaAs).
The embodiments of the present disclosure will be described with reference to the accompanying drawings. The drawing in which an element first appears is typically indicated by the leftmost digit(s) in the corresponding reference number.